Anyone or anything that gets in the way of you getting some. The cock-block can be male,female, or inanimate. Many cock-blocks can't get any themselves so they try to stop somebody else. If they ain't scorin' nobody's scorin'. No scene is too embarassing in their undying quest to prevent your action. If your buddy's a cockblock don't bring him or her.

1. My old boss, Bob is such a cock-block. He won't let any of us guys chat with the female employees.

2. My car was a cock-block. It broke down on my way to the party so I couldn't go and possibly hook-up. I had to wait for the tow-truck to come and tow me home.

When a guy moves in on a girl that another man has began courting. Usually at a party/club/bar while the other man goes for a drink or to the bathroom but can also apply to any situation where a man has expressed interest in a girl and another man moves in without regard/respect. It is a sign of grievious disrespect and may result in shunning from the male group or a serious beating/pounding/rolling or other retribution. (also Cock blocker and cock blocking)

"I was talking to this girl and my buddy sat down on the other side of her and kept butting into our conversation trying to flirt with her, I'm gonna beat that cock blocker down!"